DEEPEN, verb transitive 1. To make deep or deeper; to sink lower; as, to deepen the channel of a river or harbor; to deepen a well. 2. To make dark or darker; to make more thick or gloomy; as, to deepen the shades of night; to deepen gloom. 3. To give a darker hue, or a stronger color; as, to deepen a color; to deepen a red, blue or crimson color. 4. To make more poignant or distressing; as, to deepen grief or sorrow. 5. To make more frightful; as, to deepen the horrors of the scene. 6. To make more sad or gloomy; as, to deepen the murmurs of the flood. 7. To make more grave; as, to deepen the tones of an organ. DEEPEN, verb intransitive To become more deep; as, the water deepens at every cast of the lead.
Source: Webster's 1828 American Dictionary ↗ · public-domain · returned verbatim, no AI